Strain engineering the electronic properties of the type-II CdO/MoS2 van der Waals heterostructure

Abstract

The structural stability, electronic properties, band edge alignment and photocatalytic water splitting characteristics of the CdO/MoS2 heterostructure have been systematically investigated by first-principles calculations. The results show that the CdO/MoS2 heterostructure is a stable indirect bandgap (1.35 eV) semiconductor with a type-II band alignment and a large built-in electric field pointing from MoS2 to CdO, which greatly hinders the recombination of photogenerated carriers. Meanwhile, the CdO/MoS2 heterostructure with large carrier mobility can withstand the large biaxial strains. The band edge positions of the CdO/MoS2 heterostructure can be modulated by biaxial strain engineering. These results provide a theoretical basis for the application of the CdO/MoS2 heterostructure in photovoltaic and other electronic devices.